In combined data and energy transmission systems, in general it is necessary to comply with all fundamental guidelines concerning energy supply lines, thus including the safeguarding of individual devices within the system.
The published patent application DE 10 2012 203 828 A1 discloses a power line communication system, wherein a fuse is connected in an automatic circuit breaker. A data signal may be coupled out upstream of the fuse from current-carrying lines via a high-pass filter and be inductively fed to a power line communication modem after the coupling-out. The modem may couple the data signal into the current-carrying lines again downstream of the fuse in a current-feeding direction.
What is disadvantageous about the known system, for example, is that the fuse has to be exchanged in a manner that incurs expenditure, if that is even possible at all with tenable expenditure, when it is necessary to safeguard an electrical device specified for a maximum current that is below a triggering threshold of the fuse.
Furthermore, two elements, the high-pass filter and the modem, are required for coupling the data signal out and in again, which increases a circuit complexity and means that material consumption is increased.